In earlier studies, the inventor conducted creative experiments and invented/obtained a series of new recombinant peptides with colicin as attack point, which operationally connects a polypeptide (natural or artificial design) with identification and binding ability to target cells. For example, the new antibiotic PMC-AM1 disclosed in patent No. ZL200910092128.4, named “Novel Antibiotic Comprising an Antibody Mimetic, Its Preparation and Uses Thereof,” shows a broad-spectrum antibiotic property and has stronger antibacterial activity on Neisseria meningitidis, Multidrug-resistance Pseudomonas aeruginosa, Vancomycin-resistant Enterococcus faecalis or Methicillin-resistant Staphylococcus aureus compared to the known antibiotics. The inventor's another invention entitled “A Novel Antibiotic, Its Nucleotide Sequence, Methods of Construction and Uses Thereof,” with CN patent No. ZL200910157564.5, disclosed a series of new anti-staphylococcus antibiotics, such as PMC-SA1, PMC-SA2, PMC-SA3, PMC-SA4, PMC-SE as well as PMC-PA. In vivo and in vitro experiments, these antibiotics showed better targeting ability and stronger antibacterial activity than current antibiotics, antifungal antibiotic and chemotherapeutics drugs. Additionally compared with current antibiotics, these new antibiotics showed incomparable biological security and anti-drug-resistance characteristic.
The foresaid novel antibiotics as a whole are a kind of water-soluble proteins with 600 amino acid residues, but in which there is a hydrophobic domain with 40 amino acid residues near carboxyl terminal. Compared to preparation of other water-soluble proteins with one fold structure, there is more difficult in assembling and expressing of the novel antibiotics, which inevitably affects protein yield. It is necessary to improve current expression process to achieve high yield and priority of the novel antibiotics. It will make sense for bringing the novel antibiotics into actual clinical application and practice.